Search Publications
Nuclear spin ratios of deuterated ammonia in prestellar cores. LAsMA observations of H-MM1 and Oph D
Belloche, A.; Wyrowski, F.; Caselli, P. +6 more
Context. Molecules containing two or more hydrogen or deuterium atoms have different nuclear spin states which behave as separate chemical species. The relative abundances of these species can give clues to their origin. Formation on grains is believed to yield statistical spin ratios whereas gas-phase reactions are predicted to result in clear de…
Zero-polarization candidate regions for the calibration of wide-field optical polarimeters
Blinov, D.; Panopoulou, G. V.; Readhead, A. C. S. +14 more
Context. The calibration of optical polarimeters relies on the use of stars with negligible polarization (i.e., unpolarized standard stars) for determining the instrumental polarization zero point. For wide-field polarimeters, calibration is often done by imaging the same star over multiple positions in the field of view (FoV), which is a time-con…
Energetic seed particles in self-consistent particle acceleration modeling at interplanetary shock waves
Vainio, R.; Vuorinen, L.; Trotta, D. +2 more
Aims. The study investigates the relevance of the seed particle population in the results of particle acceleration in interplanetary shock waves, when wave–particle interactions are treated self-consistently. Methods. We employed the SOLar Particle Acceleration in Coronal Shocks (SOLPACS) model, which is a proton acceleration simulation in shocks …
A catalogue of asteroseismically calibrated ages for APOGEE DR17. The predictions of a CatBoost machine learning model based on the [Mg/Ce] chemical clock and other stellar parameters
Boulet, Thibault
Context. The formation history and evolution of the Milky Way through cosmological time is a complex field of research requiring the sampling of highly accurate stellar ages for all Galaxy components. Such highly reliable ages are starting to become available thanks to the synergy of asteroseismology, spectroscopy, stellar modelling, and machine l…
The mass distribution of stellar mergers: A new scenario for several FS CMa stars
Korčáková, D.; Kroupa, P.; Dvořáková, N. +1 more
Context. FS CMa stars belong to a diverse group of stars exhibiting the B[e] phenomenon, which manifests itself mainly by the presence of forbidden emission lines and a strong infrared (IR) excess in their spectra. Only a few tens of FS CMa stars are known and their nature is still unclear. Recently, a strong magnetic field has been discovered in …
Spatially resolved plasma composition evolution in a solar flare – The effect of reconnection outflow
Long, David M.; Brooks, David H.; Baker, Deborah +6 more
Context. Solar flares exhibit complex variations in elemental abundances compared to photospheric values. These abundance variations, characterized by the first ionization potential (FIP) bias, remain challenging to interpret. Aims. We aim to (1) examine the spatial and temporal evolution of coronal abundances in the X8.2 flare on 2017 September 1…
A fast-rotating blue straggler star in the tidal tail of the open cluster NGC 752
Chen, Li; Zhong, Jing; Qin, Songmei +3 more
Context. NGC 752 is a well-known Galactic open cluster of intermediate age. In recent works, a very long and asymmetric tail was revealed. A blue straggler star (BSS) at the periphery of the tidal tail of the cluster was subsequently identified.
Aims: We aim to perform a detailed analysis of the newly detected BSS based on the available compr…
Cosmic-ray diffusion in two local filamentary clouds
Grenier, I. A.; Kamal Youssef, F. R.
Context. Hadronic interactions between cosmic rays (CRs) and interstellar gas have been probed in γ rays across the Galaxy. A fairly uniform CR distribution is observed up to a few hundred parsecs from the Sun, except in the Eridu cloud, which shows an unexplained 30-50% deficit in GeV to TeV CR flux.
Aims: To explore the origin of this defic…
The MIRI/MRS Library. I. Empirically correcting detector charge migration in unresolved sources
Gordon, Karl D.; Law, David R.; Patapis, Polychronis +7 more
Context. The James Webb Space Telescope (JWST) has been collecting scientific data for over two years now. The Medium Resolution Spectrometer (MRS) of the Mid-InfraRed Instrument (MIRI) has been one of the telescope's most popular modes, and has already produced ground-breaking results. Scientists are now looking deeper into the data for new excit…
A CIGALE module tailored (not only) for low-luminosity active galactic nuclei
Alexander, D. M.; Lapi, A.; Comastri, A. +17 more
The spectral energy distribution (SED) of low-luminosity active galactic nuclei (LLAGN) presents unique challenges as the emission from these objects is comparable to the radiation from their host galaxy and the accretion physics involved is particularly complex. This study introduces a novel CIGALE module specifically designed to address these ch…